Cooling apparatus for hot bulk materials



Feb. 9, 1965 A. MULL 3,H69,@fl

COOLING APPARATUS FOR HOT BULK MATERIALS Filed Feb. 20, 1962 2 Sheets-Sheet 1 vemfw': fir/va J M /l A. MULL 9 COOLING APPARATUS FOR HOT BULK MATERIALS Filed Feb. 20. 1962 2 Sheets-Sheet 2 3,16%,051 CGGLHNG APPA' TUS FDR HGT BULK MATERIALS Arnold Miill, Frankfurt am Main, Germany, assignor to Metailgesellsellaft Ahtiengesellschaft, Frankfurt and Main, Germany Filed Feb. 20, 1962, Ser. No. 174,463 Claims priority, application Germany, Mar. 21, 1961, M 48,465/61 1 Claim. (Cl. 34-174) This invention relates to a cooling apparatus and, in particular, to an apparatus for the cooling of hot bulk materials, such as hot ore sinter.

Hot bulk material as, for example, ore sinter has been cooled by forming the material as a layer inclined to the vertical and contained between two gas permeable walls through which a cooling gas, such as cool air, is passed to cool the material to the desired temperature. As the material is cooled, it is desirable to prevent it from being subject to mechanical stress so that the material is not shattered and kept in its original shape. In other words, the material being cooled should be kept at rest during the cooling process. The side walls of the containing chamber are preferably divergent in a downwardly direction so that the cooled material will not bridge across the chamber and can be readily dumped from the chamber.

Heretofore known apparatuses of this type are either composed of one or more straight rows having a plurality of inclined chambers or containers rigidly connected to one another. These chambers are successively loaded with hot material, and then unloaded at the completion of the cooling process. In another form, the individual inclined containers are connected together rigidly in the form of an annulus which is rotatable around a vertical axis. Here again, the individual containers are successively loaded and unloaded each time they are rotated around a charging or dumping station.

These known apparatuses have the disadvantage in that they are subject to considerable mechanical stresses because of the high differential in temperature experienced by them, inasmuch as the hot material is charged into the containers at a temperature of at least 1,000 C. and is cooled down to 100 C. or less. The gas permeable wall upon which the hot material lies is greatly stressed by simultaneously being subjected to the heat of the ma terial on one side and the cold air drawn through the other side of the wall. During the cooling period, the apparatus is exposed to a number of different temperatures. Consequently, the contractions and expansions occurring during a relatively short period of operation cause stresses and eventually fissures in the metal structure of the apparatus.

The object of this invention is to overcome the disadvantages of the prior known apparatuses. In general, these and other objects are obtained by taking care of the thermal stresses which occur substantially entirely in that part of the overall apparatus which is in direct contact with the material being cooled, it being observed that the remainder of the apparatus is almost free of thermal stresses during long periods of operation.

According to this invention, the cooling chamber is therefore composed. of a plurality of individual baskets or containers which are not connected to one another and are merely loosely hung from the framework of the apparatus and not rigidly connected to it.

The means by which the objects of the invention are obtained are described more fully with reference to the accompanying schematic drawings, in which:

FIGURE 1 is a vertical cross-sectional view through the cooling apparatus;

3,159,05l l mented Feb. 9, 1%65 FIGURE 2 is a side view of the apparatus showing two cooling containers as seen in the direction of the arrows il-ll of FIGURE 1; and

FIGURE 3 is a cross-sectional view taken on the line Iii-ill of FIGURE 1.

The framework ll of the cooling apparatus is shown in dashed lines. The outer diagonal beams 2 are provided with bolts 3 functioning as bearing pins, and the container 4 is loosely hung from the bearing pins 3 by means of hooks 5. Thus the hooks 5 are rigidly connected to the frame 6 of container 4. Louvers 7 form the inner gas permeable wall of the container which serves as a grate. The outer wall 8 of the container is composed of the inclined plates and grate bars 9. The side walls of the container are composed of gas impermeable plates iii, note FIGURE 2. It is expedient to provide the lower ends of diagonal beam 2 with another pair of bearing pins it and to fasten a corresponding pair of hooks 12 to the container. The container is charged through the top end with hot bulk material by means of conveyor 13, and is dumped from the bottom end of the container by means of the door 14, which, in FIGURE 1, is shown in closed position by the full lines and in open position by the dashed lines.

The dimensions of the container are such that the container is hung from or supported by but a single pair of hooks. As shown in FIGURE 1, the container is hung on hooks 5 which engage the bearing pins 3. When the container becomes heated by the hot bulk material, it expands freely downwardly in the direction of the arrow a, and also expands freely upwardly in the direction of the arrow [1 because it is not secured to the framework 1, except by the engagement of the hooks 5 with the pins 3.

Also, the container expands transversely in the direction of the arrows 0, FIGURE 2, without hindrance. This is because the adjacent basket or container is spaced a distance sullicient to allow for all expansions occurring during operation. The distance between hooks 5 and 12, as shown in FIGURE 1, is such that, when the apparatus is cold, the distance is less than the corresponding distance between the pins 3 and 11. In this case, the basket or container ordinarily hang only from the upper hooks 5 and, when heated, expands downwardly. The pin lll then constitutes a simple slide bearing. in other words, pin ll does not actually function as a bearing pin or journal for supporting the container, but only serves to support that portion of the weight of the container resting on it.

However, in certain instances, it is desirable to hang the container from the lower hooks 12 rather than the upper hooks 5. in this case, the distance between pins 3 and ll is such that, when the apparatus is cold, the distance is smaller than the corresponding distance between the hooks 5 and 212. Also, in this case, the lower pin 11 is constructed as a fixed bolt or journal and the upper pin 3 functions as a single slide bearing. This latter arrangement is advantageous especially in cases where as small as possible displacement in height of the unloading door 14 is required. Sealing plates or gaskets 16 can be mounted between the stationary cold air duct 17 and the sides of the container 4 in order to prevent escape of the cooling air. Cooling is accomplished by means of cooling gases, such as air, which are introduced under forced draft through duct 17 in the direction of the arrow A.

The construction of the apparatus of this invention is well suited for either straight or round, or stationary or movable structures. The individual containers can be mounted upon a rotatable circular framework so that each container is loaded from a stationary loading station,

.3 and unloaded from a stationary unloading station. In a modified form, the containers 4 can be mounted in either a straight or curved row so that they can be successively loaded from a moving loading station, and after cooling, unloaded onto a moving unloading station.

Having now described the means by which the objects of the invention are obtained, 1 claim:

In an apparatus for the cooling of very hot bulk material such as sintered ore, said apparatus having a plurality of spaced cooling containers each composed of inner and outer vertically inclined gas permeable walls supported by a framework, means for forcing cooling gas through said walls, means for charging hot material into the upper end of each container, and means for removing cooled material from the lower end of each container, the improvement comprising bearing pins fixed to said frame- 4- Work, and hooks secured to each container and loosely engaging said pins for hanging each container from the supporting framework for free thermal expansion in all directions and independent of said framework.

References Cited by the Examiner UNITED STATES PATENTS 3,092,473 6/63 Koontz et al 34-174 FOREIGN PATENTS 1,155,283 11/57 France.

912,143 5/54 Germany. 232,416 8/ 44 Switzerland.

CHARLES SUKALO, Primary Examiner. 

